Table 2.

Resensitization of MAC-321 in PTX-resistant cell lines with MDR inhibitorsa

CompoundIC50 (nm)
KB-3-1KB-8-5KB-V1
PTX2.2 ± 0.341.9 ± 5.53100.0 ± 141.4
PTX + CL-329,7532.2 ± 0.11.3 ± 0.76.0 ± 1.4
MAC-3210.6 ± 0.040.8 ± 0.164.6 ± 2.1
MAC-321 + CL-329,7530.5 ± 0.10.5 ± 0.10.8 ± 0.1
  • a PTX-resistant KB-8-5 and KB-V1 cells and their KB-3-1 parental counterpart lines were grown in the presence of PTX or MAC-321 alone or in combination with 5 μm of the MDR reversal agent, CL-329,753 for 3 days. Growth was assessed by SRB staining as described in “Materials and Methods.” Data are reported as average IC50 ± SD for three experiments as described above.